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We here report molecular investigations of a missense mutation in the HSPE1 gene encoding the HSP10 subunit of the HSP60/ HSP10 chaperonin complex that assists protein folding in the mitochondrial matrix. The mutation was identified in an infant who came to clinical attention due to infantile spasms at 3 months of age. Clinical exome sequencing revealed heterozygosity for a HSPE1 NM_002157.2:c.217C>T de novo mutation causing replacement of leucine with phenylalanine at position 73 of the HSP10 protein. This variation has never been observed in public exome sequencing databases or the literature. To evaluate whether the mutation may be disease-associated we investigated its effects by in vitro and ex vivo studies. Our in vitro studies indicated that the purified mutant protein was functional, yet its thermal stability, spontaneous refolding propensity, and resistance to proteolytic treatment were profoundly impaired. Mass spectrometric analysis of patient fibroblasts revealed barely detectable levels of HSP10-p.Leu73Phe protein resulting in an almost 2-fold decrease of the ratio of HSP10 to HSP60 subunits. Amounts of the mitochondrial superoxide dismutase SOD2, a protein whose folding is known to strongly depend on the HSP60/HSP10 complex, were decreased to approximately 20% in patient fibroblasts in spite of unchanged SOD2 transcript levels. As a likely consequence, mitochondrial superoxide levels were increased about 2-fold. Although, we cannot exclude other causative or contributing factors, our experimental data support the notion that the HSP10-p.Leu73Phe mutation could be the cause or a strong contributing factor for the disorder in the described patient.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2008.11.001 Byline: Mette Findal Andreasen (a), Rasmus Telving (a), Rune Isak Dupont Birkler (a), Bente Schumacher (b), Mogens Johannsen (a) Keywords: Bromo-Dragonfly; LC-MS/MS; UPLC-TOFMS; Intoxication Abstract: This paper reports a fatal overdose case involving the potent hallucinogenic drug Bromo-Dragonfly (1-(8-bromobenzo[1,2-b; 4,5-b']difuran-4-yl)-2-aminopropane). In the present case, an 18-year-old woman was found dead after ingestion of a hallucinogenic liquid. A medico-legal autopsy was performed on the deceased, during which liver, blood, urine and vitreous humour were submitted for toxicological examination. Bromo-Dragonfly was identified in the liver blood using UPLC-TOFMS, and was subsequently quantified in femoral blood (0.0047mg/kg), urine (0.033mg/kg) and vitreous humour (0.0005mg/kg) using LC-MS/MS. Calibration standards were prepared from Bromo-Dragonfly isolated from a bottle found next to the deceased. The structure and purity of the isolated compound were unambiguously determined from analysis of UPLC-TOFMS, GC-MS, HPLC-DAD,.sup.1H and.sup.13C NMR data and by comparison to literature data. The autopsy findings were non-specific for acute poisoning. However, based on the toxicological findings, the cause of death was determined to be a fatal overdose of Bromo-Dragonfly, as no ethanol and no therapeutics or other drugs of abuse besides Bromo-Dragonfly were detected in the liver, blood or urine samples from the deceased. To our knowledge, this is the first report of quantification of Bromo-Dragonfly in a biological specimen from a deceased person. This case caused the drug to be classified as an illegal drug in Denmark on 5th December 2007. Author Affiliation: (a) Section for Toxicology and Drug Analysis, Institute of Forensic Medicine, University of Aarhus, Brendstrupgaardsvej 100, DK-8200 Aarhus N, Denmark (b) Section for Forensic Pathology and Clinical Forensic Medicine, Institute of Forensic Medicine, University of Aarhus, Brendstrupgaardsvej 100, DK-8200 Aarhus N, Denmark Article History: Received 27 May 2008; Revised 31 October 2008; Accepted 3 November 2008

The accuracy of any analytical method is highly dependent on the selection of an appropriate calibration model. Here, we present CCWeights, an R package for automated assessment and selection of weighting factors for accurate quantification using linear calibration curve. Additionally, CCWeights includes a web application that allows users to analyze their data using an interactive graphical user interface, without any programming requirements. The workflow and features of CCWeights are illustrated by the analyses of two datasets acquired by liquid chromatography-mass spectrometry (LC-MS). The resulting quantification table can be directly utilized for further model assessment and subsequent data analysis. [ABSTRACT FROM AUTHOR]